Selective fluid-distributing device



June 9, 1959 P. AUDEMAR 2,889,351

sELEcTxvE FLUID-DISTRIBuT-ING DEVICE Filed May 25, 1955 SELECTIVEFLUID-DISTRIBUTING DEVICE Pierre Audemar, Mulhouse, Haut-Rhin, France,assignor to Societe Alsacienne de Constructions Mecaniques, Mulhouse,Haut-Rhin, France, a company of France The present invention relates topressure fluid distributors.

The main object of the invention is to provide a double pressure tluiddistributor with a single control lever adapted to selectively assumeone out of four predetermined positions in order to secure respectively:

(1) The admission of pressure iluid into a rst enclosure such as one ofthe chambers of a double acting jack, while a second enclosure, such asthe second chamber of said jack remains open;

(2) removing pressure fluid out of said iirst enclosure while the secondenclosure remains open;

(3) introducing pressure fluid into said second enclosure while the rstenclosure remains open;

(4) maintaining the pressure fluid present in the rst enclosure Whilethe second remains open.

To this end the distributor according to the present invention is mainlyconstituted by two pairs of valves mounted in a uid tight body incommunication with both enclosures, with the source of pressure fluidand with a zone of low pressure, and each adapted to be opened by a pushrod, and a control lever adapted to operate said push rods so as toestablish the communications which correspond to the four aforesaidcombinations.

Other objects of the invention are to provide a number of constructionalarrangements, such as the provision of check-valves and the design ofthe single control lever and the push rods for the valves, in ordermainly to secure a perfect seal and a great simplicity in the control ofthe distributor.

Other and further objects and advantages of the invention will beapparent to those skilled in the art, from a consideration of thefollowing description of one specific embodiment of the invention, shownby way of example in the accompanying drawings, in which:

Figure l is a longitudinal section of a distributor according to theinvention in its neutral position.

Figures 2, 3 and 4 show, on a smaller scale, the same distributor inthree diierent positions, namely a position in which it provides for theadmission of pressure fluid into a first enclosure connected with thedistributor, a position in which said pressure iluid is directed out ofsaid enclosure, a second enclosure being connected to an exhaust port ineach of these two aforesaid positions, and finally a position in whichpressure fluid is admitted into the second enclosure while the rstenclosure is cnnected to the exhaust, and

Figure 5 is a fragmentary section taken on the line 5-5 of Figure l, ona larger scale.

Referring rst to Figure l, it will be seen that the distributoraccording to the invention comprises a single body 1 having sixcylindrical recesses 2, 3, 4, v5, `6, 7, the perforated bottoms of whichserve as seats for ball valves 8, 9, 10, 11, 12, 13 urged toward theirrespective seats by springs such as the spring indicated at 16 whichbears at one end against the ball valve 13 and at its other end againstthe inner face of a screw threaded plug 17 which ts Patent closes therecess 7. All the valves have a similar structure and operate in thesame manner.

Both valves 8 and 9 are inlet valves the upstream side of whichcommunicates with a pipe 21 into which a pump 22 is adapted to deliver afluid under pressure, for instance oil, from a tank 23 through a pipe24.

Both valves 10 and 11 are exhaust valves, the downstream side of whichcommunicates with the tank 23 through a pipe 25 and the valves serve forreturning the oil back to the tank.

Both valves 12 and 13 are check-valves, the upstream side of whichcommunicates with the downstream side of the inlet valves 8 and 9respectively, through channels 26 and 27 drilled in the body 1 andclosed by screw threaded plugs 28. The downstream side of thecheck-valves 12 and 13 communicates with the upstream side of theadjacent exhaust valves 10 and 11 through channels 31 and 32respectively. The upstream side of the exhaust valves 10 and 11 alsocommunicates with two utilization enclosures 50, 51 through pipes 33 and34 respectively, so that said pipes are adapted to be placed intocommunication with the pipe 21 which serves for admitting pressure uidthrough the inlet valves 8 and 9 and the corresponding check-valves 12and 13.

The check-valves 12 and 13 are operated only by the pressure of thefluid, Whereas the other four valves are adapted to be selectivelyoperated by push-rods 36, 37, 38, 39 mounted for sliding movement incorresponding bores of the body 1 and capable of pushing the ballsagainst the action of their respective return springs in order to removethe Valves from their seats. The pushrods cooperate with a singlecontrol lever 42 pivoted on a spindle 43 (see also Figure 5) which isjournalled in the body 1 inside a bore 44 closed by a screw threadedplug 45. The control lever 42 may be operated through a control arm 46secured to one end of the spindle 43 which extends out of the body 1through two bores each provided with a sealing device 43.

By virtue of this arrangement, the small amount of pressure iluid likelyto leak along the push-rods is collected within the bore 44, and thebody of the distributor being, as a whole, kept fluid-tight.

The lengths of the various push-rods are such that, when the lever 42assumes the position represented in Figure 1, i.e. on the axis of thebore 44 of the body, the three push-rods 36, 38 and 39 are in contactwith said lever, or, otherwise stated and more speciiically, both pushrods 36 and 38 are nearly in contact with the lever 42 in order to allowthe balls 8 and 10 to rest against their seats, whereas the push-rod 39is positively pushed by the lever 42 in order to keep the ball 11 awayfrom its seat. Finally, the pusher rod 37 is short enough for the valve9 not being operated upon, the lever 42 being rocked an angle a (seeFigure 3) counterclockwise (looking at the drawing), an angle which,however, is suiiicient for permitting actuation of the valve 10.Furthermore, the arrangement is such that when the lever 42 assumes theposition which is shown in Figure 3, the valve 11 does not yet rest uponits seat. v

However, when the lever 42 has been rocked an angle m a in the samedirection (Figure 4), the valve 9 is opened and the valve 11 closed.

Finally, when the lever 42 assumes a fourth position, namely thatillustrated in Figure 2, in which said level is inclined in the oppositedirection, both valves 8 and11 are open.

By Way of illustration, a pressure gage 48 has been represented asmounted on the pipe 33 in order to indicate the value of the pressurethat prevails within the enclosure 5t).

The operation of the distributor which hasV just been described is asfollows:

When the single control lever 42 assumes its neutral position, i.e. thatillustrated in Fig. 1, the enclosure 5,0 is shut off since the Valves 10and 12 are closed, whereas the enclosure 51 is connected to the returnpipe 25 through the pipe 34 and valve 5 now open. The pressureprevailing within the enclosure 50 may be read on the pressure gage 48.It will be noted that, in this position of the control lever, both inletvalves S and 9 are now applied against their respective seats, not onlyby the action of their springs but also under the effect of the pressureoil which is present upstream of these valves within the feed pipe 21leading from the pump 22.

If it is desired to increase the amount of pressure uid present withinthe enclosure 5G, the control lever 42 is rocked clockwise (looking atthe drawing) in order to be brought into the inclined positionillustrated in Figure 2. The inlet valve 8 is operated under the actionof the pusher rod 36 and some pressure oil flowing from the feed pipe 21then iiows through said valve, channel 27, check-valve 6 and pipe 33 inorder to reach the enclosure 50. The pressure that prevails in theenclosure S0 then rises and, when the desired pressure is reached, thecontrol lever 42 is brought back to its neutral horizontal position ofFig. l. It will be noted that, when the control lever assumes theposition shown in Figure 2, the enclosure 51 maintains its communicationwith the tank 23 through the pipe 34, open valve 11 and return pipe 25.In the case when the enclosures 50 and 51 are constituted by the twochambers of a double acting jack, the pressure fluid contained in thesecond of said chambers is thus freely exhausted and does not interferewith the admission of lluid into the former.

In contradistinction, if it is desired to reduce the amount of pressureuid contained within the enclosure 50, the control lever is rocked anangle ot in the opposite direction, as indicated in Figure 3, so thatonly valve 10 is opened while valve 11 does not close. A portion of thefluid contained in the enclosure 50, thus, may be discharged throughpipe 33, open valve 10 and return pipe back to the tank 23. It is to bepointed out that, in this position of the control lever, the enclosure51 communicates with the tank 23, since pipe 34 is itself incommunication with the return pipe 25 and tank 23 through the valve 11which is kept open. Under such conditions, and still in the case of adouble acting jack, no negative pressure likely to hinder the dischargeof fluid from the first enclosure 5t) would be created. After thepress-ure in the enclosure 50 has dropped to the desired value, or else,after the desired amount of fluid has been removed, the lever is broughtback to its horizontal position (Fig. l) in order again to lock theinlet circuits to the enclosure 50.

Finally, when it is desired to introduce more fluid into the enclosureS1, it is suflcient to increase the inclination of the control lever inthe same direction in order to bring it into the position illustrated inFig. 4. In this position, the valve 9 is open and the pressure iluidilowing from the feed pipe 21 passes through said valve, channel 26,check-valve 13, channel 32, pipe 34 and back to the enclosure 51. In themeantime, the fluid occasionally present in the enclosure 5t) is able toflow into the tank 23 through the pipe 33, open valve lll and returnpipe 2S. Thus, in the case of the jack, the first enclosure remains openand does not interfere with the movement of the piston under the actionof the uid introduced into the second enclosure.

In order again to introduce fluid into the enclosure 50,

as represented in Figure l, it, of course, would be suicient, as statedpreviously, to bring the control lever into the admission positionindicated in Figure 2.

It will be readily seen that this device, the operation of which is verysimple, has a very flexible control and affords quick operations. Asmany changes could be made in the above construction, and manyapparently widely different embodiments of this invention could be madeWithout departing from the scope of the claim, it is intended that allmatter contained in the above description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

Thus, the distributor of the invention could be used with any suitablefluid other than oil, either a liquid or a gas, and the pressuresprevailing in the enclosures 50, 51 may be independent or, on thecontrary, a function of each other (double acting jack).

Finally, it is obvious that, in the position of Figure 1, thecommunication between the second enclosure 51 of Figure l and the tankcould be desirably shut oi by means, for instance, of a mere valveinserted in the pipe 34 so as to shut olf both enclosures simultaneously(case in which it would be desired to lock a double acting jack in aparticular position thereof).

What I claim is:

A distributor for selectively feeding pressure fluid into one of twoenclosures, while controlling escape of fluid from the other one,comprising, in combination, a fluidtight body, first and secondspring-loaded inlet valves housed Within said body, fluid-conductingmeans leading to said inlet valves and adapted to be simultaneouslyconnected with a source of pressure fluid, Huid-conducting means leadingfrom said inlet valves and adapted to be separately connected to saidenclosures, a rst and a second exhaust spring-loaded valves housedwithin said body, fluid-conducting means leading to said exhaust valvesand adapted to be separately connected with said enclosures andfluid-conducting means leading hom said exhaust valves and openingoutside said body, a 4-position control lever pivotally mounted in saidbody and operable from outside, and linkage means to operatively connectsaid control lever with said valves to selectively establish one of fourvalve congurations viz, a rst conguration in which only said secondexhaust-valve is open, a second configuration in which only said firstinlet valve and said second exhaust valve lare open, a thirdcomiguration in which only said rst and second exhaust valves are openand a fourth configuration in which only said second inlet valve andsaid lirst exhaust valve are open, the linkage means being defined byfour operating rods, respectively interposed between the control leverand said valves, and adapted to be operated by the control lever, uponcorresponding movement thereof from neutral position with a sameleverage, the operating rods of said rst inlet valve and said rstexhaust valve having a same length, the operating rod of the secondinlet valve being shorter than said length and the operating rod of thesecond exhaust valve being longer than said length.

References Cited in the iile of this patent UNITED STATES PATENTS1,751,276 Karibo et al Mar. 18, 1930 2,293,555 Mercier Aug. 18, 19422,671,433 Meddock Mar. 9, 1954 FOREIGN PATENTS 587,159 Great Britain1947 598,078 Great Britain 1948

